[Dbix-class] Moose

[David Ihnen]

On Sun, Jul 18, 2010 at 1:39 PM, Leandro Hermida <softdev at leandrohermida.com
> wrote:

> On Sun, Jul 18, 2010 at 7:49 PM, Peter Rabbitson <rabbit+dbic at rabbit.us<r=
abbit%2Bdbic at rabbit.us>
> > wrote:
>
>> On Sun, Jul 18, 2010 at 02:40:47PM +0200, Leandro Hermida wrote:
>> > very good points and makes a lot of sense.  If I can ask a more general
>> > question then, why do ORMs exist in the first place and why are they so
>> > popular vs using a object persistence mechanism?  There must be some
>> serious
>> > advantage to using them.
>> >
>>
>> Because there yet does not exist a persistent object store, that can be
>> asked to fetch "all objects which have related objects whose attribute X
>> is Y", and which will do so by *transparrently* using native SQL methods
>> (namely GROUP BY over a joined resultset). Matt Trout is working on the
>> foundation of just such a "mapper", but this is a very very hard problem
>> to get right, so progress is slow.
>>
>
> I know this might sound sacrilegious, but established frameworks like
> Hibernate have solved this problem and the code is freely available, I th=
ink
> it would be easier to see how such complex ORM details are done there as a
> starting point and then go from there other than starting from completely
> scratch?
>

I'm confused, are you saying that Hibernate can be asked to fetch all
objects which have related objects who attribute X is Y and it solves this
problem by transparently using native SQL methods (like GROUP BY over a
joined resultset)?

Or are you saying that Hibernate can fetch all objects using some other
method of query and retrieval?

David

-- =

"If only I could get rid of hunger by rubbing my belly" - Diogenes
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